On Mon, 2007-12-17 at 11:07 +0000, James Freer wrote:
However what is a "filtered mains strip"? Is that the same as a Surge Protector? My machine is in a room where there is only one socket - i'm using a 4 socket surge protector and extension. From the electrical side i can't see how a surge protector can affect it. No problems with 7 months use.
It would depend on the quality and effectiveness of the mains filter in question. Which can be different to a simple surge protector, remember a fuse is technically a "surge protector"..typically the cheaper ones may just have varying degrees of transient suppression and not actually "filter" the mains".
A textbook design of a proper mains filter might add say 1 millihenry of series inductance with perhaps 20 or so nF of parallel capacitance and perhaps 3-5 nF of capacitance tying the two rails down to ground, typically then the designer might add a voltage dependant resistor to try and catch the odd transient. Granted the capacitance and inductance are all pretty low figures but when the high frequency carrier is in a completely different range to the mains frequency and at a much lower amplitude it would be easy to see how these components wouldn't do the carrier signal any good.
Certainly I have known at least one type of filtered mains strip to have quite a serious negative impact on the homeplug kit. However as I say, if your strip is only a surge protector trying to catch transient spikes then it may have little to no effect.
Kind regards Wayne